Been there done that...
I've just finished this same procedure on my 85. Getting the valve covers off is a real PITA, but easily doable in an afternoon. I had to move my alternator and get my drivers side cover out of the engine cavity.
If memory serves me correctly, the proper torque is about 80 - 120 in/lbs, (I'll verify when I get back to the house and can look at the manual...I'll repost if I'm incorrect). Be careful...your heads are aluminum and its excessively easy to strip out the holes, and that's no fun at all (again....been there). When it was all said and done, I simply set the valve cover bolts good and firm (i.e. did not torque them). The valve covers do not have that much oil pressure on them when the engine is running so I just tightened them good and firm and let the gasket do its work (Disclaimer: It is always better to follow torque specs...do as I say, not as I do).
Make sure you clean off the mating surfaces really well to remove any leftover gasket or sealant. Also its a pretty good idea to change your oil and filter after this procedure, as you will likely get some gunk down in the oil during the process of cleaning off the mating surfaces.
Good luck.
Trey